Phenanthrene is a polycyclic aromatic hydrocarbon (PAH) composed of three fused benzene rings. It has the chemical formula C14H10 and appears as a white crystalline solid. Phenanthrene is commonly found in coal tar and is produced during the incomplete combustion of organic materials. This compound is used in various applications, including the production of dyes, plastics, and pesticides. Due to its structure, phenanthrene can participate in chemical reactions that lead to the formation of other compounds. However, it is also known to be a potential environmental pollutant and can pose health risks if inhaled or ingested.